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The Food and Drug Administration (FDA) announced on Thursday that two people were arraigned for smuggling “adulterated and misbranded” prescription cancer drugs from Turkey into the U.S. The drugs the individuals were attempting to bring into the country are not FDA-approved.

The two who were charged were Turkish citizens, Ozkan Semizoglu, 39, and Sabahaddin Akman, 40, and they were arrested in Puerto Rico. “This case shows that those who prey on innocent patients in the United States, even from outside our borders, are subject to criminal prosecution,” John Roth, director of the Office of Criminal Investigations in the FDA’s Office of Regulatory Affairs, stated in an FDA news release. “The assistance of our international partners was critical in carrying out the undercover operation that led to the arrest of these individuals.”

Semizoglu and Akman hid the illegal identity of the drugs by false customs declarations, claiming the shipments were “gifts,” “documents,” or “product samples,” according to the FDA news release. Some of the larger drug packages were broken up into smaller ones to avoid suspicion.

The two men are charged with one conspiracy count, as well as three counts of smuggling illicit drugs into the U.S. Each smuggling count involves a penalty of up to 20 years in prison, with the possibility of fines up to $250,000.

The FDA worked closely with other international forces, including German government offices and special agents of the U.S. Department of State.

Last year, the FDA announced to tighten control over illegal online pharmacies, which sell dangerous medications to unsuspecting American consumers. In June of last year, the FDA shut down over 9,600 websites that illicitly sell unapproved prescription medications. Most of the websites discovered and shut down were involved in an enormous organized criminal network that claimed to be “Canadian Pharmacies,” though they used fake licenses and certifications to make it seem they were real.

“Illegal online pharmacies put American consumers’ health at risk by selling potentially dangerous products,” Roth said in a press release. “This is an ongoing battle in the United States and abroad, and the FDA will continue its criminal law enforcement and regulatory efforts. The agency is pleased to participate in Operation Pangea to protect consumers and strengthen relationships with international partners who join in this fight.” Operation Pangea is an international “week of action” that battles online counterfeit and illegal drugs, and is coordinated by INTERPOL.